The sidewall members, roof members and floor members of trailers and other over-the-road vehicles are constructed so as to distribute and carry the loads normally carried by such vehicles. All joints and connecting assemblies between the sidewalls, roof members and floor members have to be carefully constructed to prevent uneven load distribution and the establishment of uneven bending moments which might cause buckling and distortion of the sidewalls.
The structural problem relative to the wall, roof and floor construction, as well as the joint assemblies, are more acute when the trailer is a refrigerator trailer and the walls, roof and floor members are insulated with various components which are generally incapable of supporting sub stantial weight or handling uneven weight distribution or bending moments. In the event that such refrigerated vehicles have post-free walls comprised of relatively thin inner and outer plastic panels with insulating foam therebetween, the walls must carry loads without the support normally offered by posts. In such a situation the configuration of the bottom rail of the wall is critical.
Accordingly, the broad object of the present invention is an improved sidewall construction for over-the-road trailers and other vehicles, especially refrigerator trailers.
Another object of the present invention is an improved bottom rail construction having a stress transfer relationship with its associated sidewall components that exhibits an evenly balanced bending moment on the connection between inner and outer panels of the sidewall and the bottom rail.
A further object of one embodiment of the present invention is to provide an improved bottom rail construction which permits conventional riveting from one side of the sidewall members.
The aforesaid objects are achieved by means of an improved bottom rail that is attached to the floor of the trailer and secures load-bearing, post-free sidewalls thereto. Each of the sidewalls comprises a pair of substantially parallel, vertically extending, horizontally spaced load-bearing, plastic panels. Foam insulation is injected between the panels forming the sidewalls. The bottom rail has a vertical flange for attachment to the floor which lies between the wall panels. A pair of L-shaped flanges are positioned on opposite sides of the vertical flange, each of which is attached to one of the sidewall panels. The horizontal portions of the L-shaped flanges are of substantially equal dimension so as to transmit loads substantially equally to the spaced sidewall panels thereby to apply substantially equal bending moments to the sidewall panels.
Further objects, features and advantages of the present invention will become apparent from the following description viewed in accordance with the accompanying drawings.